docs: correct a spelling mistake

[leonleerl]

Overview

While reading the document from the website, I found a word misspelled. I changed the wrong word to "empty".

Checklist before requesting a review

• [N] I have updated the unit tests based on the changes I made
• [N] I have updated the docs (TSDoc / README / global doc) to reflect my changes
• [N] I have updated the local app configs if needed
• [N] I have performed self-QA of my feature by testing the apps and packages and made sure that :
  • No regression or new bug has occurred
  • The acceptance criteria listed in the ticket are met
  • Self-QA was made on both desktop and mobile